.borderBox {
    position: absolute;
    background: transparent;
    border: 2px dashed blue;
    cursor: move;
}
.borderBox-dot {
    position: absolute;
    display: block;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background-color: red;
    border: 2px solid green;
}